Yabla

昨天 zuótiān

一直 yīzhí

都 dōu

不 bù

知道 zhīdào

是 shì

冬至 Dōngzhì

Yesterday, all that time, I hadn't realized it was winter solstice.

根据 gēnjù

太阳 tàiyáng

在 zài

两 liǎng

个 gè

冬至 Dōngzhì

日 rì

之间 zhījiān

的 de

运行 yùnxíng

情况 qíngkuàng

划 huá

出 chū

一 yī

年 nián

One year is calculated based on the sun's movement between two winter solstices.

每年 měinián

冬至 Dōngzhì

到 dào

大寒 Dàhán

Every year from Dongzhi (the arrival of the Winter) to Dahan (the coldest day of the year)